In personal computers or common hand-held smart mobile devices, the memory is an essential element. As the semiconductor technology is improved on manufacturing process and product yield rate, the memory efficiency is also advanced.
In the hand-held smart mobile device and the computer, multi-channel memory technology is used to improve the memory efficiency. In the multi-channel memory technology, a plurality of parallel memory channels are between the dynamic random access memory (DRAM) and the memory control circuit to improve data throughput.
Each channel of the multi-channel memory is independent. However, the access latency between the channels may be different due to manufacture process variations. Or, even for the same channel, the access latency may be varied because of the usage time, the temperature or the interface between the memory and the memory control circuit.
Built-in self-test (BIST) circuit is widely used in many memory products for memory test. BIST circuit can improve test quality with low test cost.
How to test the multi-channel memory in a low-cost, fast and accurate way is an important issue.